[llvm] [VPlan] Model branch cond to enter scalar epilogue in VPlan. (PR #92651)

[via llvm-commits]

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@@ -448,11 +448,13 @@ VPBasicBlock::createEmptyBasicBlock(VPTransformState::CFGState &CFG) {
 }
 
 void VPIRBasicBlock::execute(VPTransformState *State) {
-  assert(getHierarchicalSuccessors().empty() &&
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ayalz wrote:

Update to assert empty-or-single?

https://github.com/llvm/llvm-project/pull/92651